Time-setting device for setting timing wheels in a digital interval timer

ABSTRACT

A time-setting device for setting the timing wheels in a digital interval timer comprises an operating lever mounted for pivotal movement between a timing wheel of a time-indicating system and a timing wheel of a reference time-indicating system. The operating lever is mounted for pivotal movement in one direction towards one timing wheel and for pivotal movement in the other direction towards the other timing wheel and a biasing spring continuously biases the operating lever into a middle position intermediate the timing wheels. A ratchet wheel is affixed to each timing wheel and a pair of pawls are mounted on oposite sides of the operating lever so that movement of the operating lever towards one timing wheel causes one pawl to engage with one ratchet wheel and effect angular displacement of the ratchet wheel along with its associated timing wheel through predetermined angular increments whereas movement of the operating lever towards the other timing wheel causes the other pawl to engage with the other ratchet wheel and effect angular displacement of the other ratchet wheel along with its associated timing wheel through a predetermined angular increment. Each timing wheel may be selectively positioned in the desired angular position by repeatedly moving the operating lever until the desired position is reached.

Iflitai et aI.

Oct. 2, 1973 1 1 TIME-SETTING DEVICE IFOR SETTING TIMING WHEELS IN A DIGITAL INTERVAL TIMER [75] Inventors: Kiyoshi Kitai, Tokyo; Mitsuo Koyama, Yotsukaido-machi; Shogo Kato, Chiba-ken; Yuzuru Takazawa, Tokyo; Shinji Nagaoka, Yotsukaidomachi, all of J apan [73] Assignee: Seiko Koki Kabushiki Kaisha,

Tokyo, Japan 22 Filed: Nov. 20, 1972 21 Appl. No.: 307,867

[ Foreign Application Priority Data Nov. 18,1971 Japan ..46/9l888 [51] Int. Cl G04f 3/02, G04b 19/02 [58] Field of Search 58/6, 16 R, 38, 125 C,

v [56] References Cited UNITED STATES PATENTS 3,143,847 8/1964 Lee, Jr. 58/229 3,662,535 5/1972 Hedrick et a1. 58/395 Primary lfxamin0r--George H. Miller, Jr. AlmrneyRobert E. Burns et a1.

[57] ABSTRACT A time-setting device for setting the timing wheels in a digital interval timer comprises an operating lever mounted for pivotal movement between a timing wheel of a time-indicating system and a timing wheel of a reference time-indicating system. The operating lever is mounted for pivotal movement in one direction towards one timing wheel and for pivotal movement in the other direction towards the other timing wheel and a biasing spring continuously biases the operating lever into a middle position intermediate the timing wheels. A ratchet wheel is affixed to each timing wheel and a pair of pawls are mounted on oposite sides of the operating lever so that movement of the operating lever towards one timing wheel causes one pawl to engage with one ratchet wheel and effect angular displacement of the ratchet wheel along with its associated timing wheel through predetermined angular increments whereas movement of the operating lever towards the other timing wheel causes the other pawl to engage with the other ratchet wheel and effect angular displacement of the other ratchet wheel along with its associated timing wheel through a predetermined angular increment. Each timing wheel may be selectively positioned in the desired angular position by repeatedly moving the operating lever until the desired position is reached.

8 Claims, 6 Drawing Figures PATENTEDUBT "elm SHEET 2 BF 2 TIME-SETTING DEVICE FOR SETTING TIMING WIIlElEIJS IN A DIGITAL INTERVAL TIMER The present invention pertains generally to a timesetting device for a timer and more particularly to a time-setting device for setting the timing wheels in a digital interval timer.

Digital interval timers are known in the art and have a time-indicating system for indicating the time and a reference time-indicating system for indicating a reference time which is to be set into the timer. Such timers also have some type of time-setting device for setting the reference time in the reference time-indicating system as well as a device for setting the actual time of the timer clock which is displayed by the time-indicating system. It is well-known in the art to use separate timesetting devices to effect setting of the reference time and the actual time and the use of two devices renders the timer more complex and expensive.

It is therefore a primary object of the present invention to provide a time-setting device for a digital interval timer which is selectively operative to set either the actual time or the reference time. p

It is a further object of the present invention to provide a time-setting device for selectively setting the timing wheels in a digital interval timer and which is simple in construction yet reliable in operation.

It is yet another object of the present invention to provide a time-setting device for setting the timing wheels in a digital interval timer in response to simple up and down movement of an operating lever thereby greatly simplifying the time setting operation.

The above and other objects are carried out by a time-settingdevice comprising a pivotal operating lever mounted for pivotal movement between a pair of timing wheels. A pair of pawls are symetrically disposed on opposite sides of the operating lever and coact with ratchet wheels affixed to the timing wheels such that manual pivotal movement of the operating lever in opposite directions causes the pawls to individually engage with the ratchet wheels and effect angular displacement of the timing wheels. A biasing spring constantly urges the operating lever into anonworking position intermediate the two timing wheels so that when the operating lever is manually pivoted towards one of the timing wheels and then released, the biasing spring will return the operating lever to its nonworking position in readiness to be driven through another working stroke.

Other objects and advantages of the present invention will become apparent upon a reading of the following specification and claims which describe the presently preferred embodiments of the invention in sufficient detail to enable those persons ordinarily skilled in the art to readily understand the principles, construction, operation, function and advantages of them when read in conjunction with the accompanying drawings, wherein like reference characters denote like parts in the various views, and wherein:

FIG. l is a front plan view of a digital interval timer embodying the time-setting device of the present invention;

FIG. 2 is a cross-section of the digital timer shown in FIG. l and showing one embodiment of a time-setting device constructed in accordance with the principles of the present invention;

FIG. 3 is a cross-section of a digital timer employing another embodiment of time-setting device of the present invention;

FIG. 4 is a side view of another embodiment of operating lever used in the time-setting device of the pres ent invention;

FIG. 5 is a side view of a further embodiment of an operating arm of a time-setting device; and I FIG. 6 is a rear view of the operating lever and biasing means shown in FIG. 3.

A digital interval timer employing the time-setting device of the present invention is shown in FIG. I. The digital interval timer 10 comprises a time-indicating system for indicating in digital form the time of the clay and a reference time-indicating system for indicating in digital form the time at which the timer is to perform some function, such as close a switch, sound an alarm, etc. Only the front face of the digital timer is shown in FIG. l and such includes a front plate 11 having therein an upper window 12 for indicating the time on the timer clock and a lower window 13 for indicating the reference time which is set into the time in a manner hereinafter described.

The time-indicating system and the reference timeindicating system each comprise a set of three timing wheels each containing therearound digital timing indicia so that as the timing wheels are angularly displaced, they provide a visible time indication. Each set of timing wheels comprises a minute timing wheel, a 10- minute timing wheel and an hour timing wheel so that the actual time is indicated in hours and minutes and the desired reference time to be selected by the digital timer may be selected in hours and minutes.

In accordance with the present invention, the digital interval timer includes a time-setting system for selectively setting the time of both the time-indicating system and the reference time-indicating system independently of each other. The time-setting system includes a set of operating levers 15, 16 and 17 positioned between the upper window 12 and the lower window 13. Each operating lever functions to selectively set the time indicated by one timing wheel in each of the timeindicating system and the reference time-indicating system. r

The operating lever 15 is positioned between the minute timing wheel 20 of the time-indicating system and the minute wheel 22 in the reference timeindicating system and the lever is mounted for both upward movement to angularly displace the upper timing wheel 20 and the downward movement to angularly displace the lower timing wheel 22. In a like manner, the operating levers 116 and 117 are mounted for upward and downward movement to angularly displace their associated timing wheels. The digital interval timer also includes a push-button 18 for placing the time-setting system in an operative state so that the reference time set by the reference time-indicating system is detected and a suitable output signal is developed indicating that the reference time coincides with the time indicated by the time-indicating system.

One embodiment of the present time-setting system constructed in accordance with the principles of the present invention is shown in FIG. 2. FIG. 2 is a crosssectional view of a portion of the digital timer 10 shown in FIG. 1 and illustrates the coaction between the operating lever I5 and its associated minute timing wheels. The minute timing wheels 20 of the time-indicating system is rotatably mounted on a shaft 21 in such a manner that the digital timing indicia contained thereon successively moves past the upper window 12 in re sponse to angular displacement of the timing wheel. In a similar manner, the minute timing wheel 22 of the reference time-indicating system is rotatably mounted on a shaft 23 so that the ditial timing indicia contained thereon revolves past the lower window 13 in response to angular displacement of the timing wheel. Though not shown in the drawing, the -minute timing wheels and the hour minute wheels are mounted relative to each other in a similar manner.

A ratchet wheel 25 is rotatably mounted on the shaft 21 and is affixed to the minute timing wheel for rotation therewith. A click or detent member 26 is pivotally mounted adjacent the minute timing wheel 20 and is biased into engagement with the ratchet teeth on the ratchet wheel by a biasing spring 27. The detent member 26 coacts with the ratchet teeth to permit clockwise rotation of both the ratchet wheel and the timing wheel but prevents their counterclockwise movement and in addition, the detent member coacts with the ratchet teeth to stop the timing wheel 20 in predetermined precise positions. A rotationally driven gear 28 meshes with gear teeth on the minute timing wheel 20 for rotationally driving the timing wheel and the gear 28 is driven by a motor which is not shown in the drawings.

A ratchet wheel 29 is affixed to the minute timing wheel 22 and is rotatable about the shaft 23. A detent member 30 is pivotally mounted adjacent the minute timing wheel 22 and coacts with the ratchet teeth on the ratchet wheel 29 to prevent clockwise rotation thereof yet readily permits counterclockwise rotation of the ratchet wheel and the timing wheel 22. A biasing spring 31 coacts with the detent member 30 to bias same into contact with the ratchet wheel and the detent member functions like the detent member 20 to effect precise positiioning of the ratchet wheel and hence the timing wheel 22.

The operating lever 15 has the configuration shown in FIG. 2 and is pivotally mounted about a pin 32 for both upward pivotal movement and downward pivotal movement. The lever has a manually graspable knob 33 which projects outwardly from the front plate 1 1 of the digital timer casing and a suitable slot is provided in the front plate to enable vertical up and down movement of the operating lever. The other end of the operating lever is bifurcated into two resilient prongs 34, 35 and either the entire operating lever or just the prongs are formed of resilient material, such as polypropylene. A stationary pin 36 is positioned between the prongs and functions to resiliently separate the prongs a limited extent thereby biasing the operating lever 15 into the position shown in FIG. 2. This position corresponds to the middle position or nonworking position of the lever.

A pair of arcuate arms 37, 38 each extend outwardly from the main body portion of the lever 15 in a direction towards respective ones of the ratchet wheels. At the end tip of the operating lever arm 37 is a pawl 39 and the pawl coacts with the ratchet wheel 25 in response to upward displacement of the operating lever to angularly advance the ratchet wheel in a clockwise direction. In a similar manner, a pawl 40 is positioned at the end portion of the operating lever arm 38 and coacts with the ratchet teeth on the ratchet wheel 29 to angularly displace the ratchet wheel in a counterclockwise direction in response to vertical downward movement of the operating lever 15.

The operation of the time-setting system of the invention will now be described with reference to FIG. 2. FIG. 2 does show the state of the various components when the operating lever 15 is biased into its nonworking position by the resilient prongs 34, 35 and the pawls 39, 40 are maintained out of engagement with their respective ratchet wheels. At this time, the actual time on the timer clock is displayed through the upper window 12. Thus, the time-indicating system functions as a digital clock and displays the time in digital form through the window 12. At the same time, the reference time indicia are visible through the lower window 13.

Assuming now that it is desired to correct or set the time in the time-indicating system, the knob 33 of the operating lever 15 is manually urged upwardly against the spring force exerted by the resilient prongs 34, 35 causing the pawl 39 to engage with the ratchet teeth on the ratchet wheel 25 afterwhich the ratchet wheel along with the minute timing wheel 20 are angularly displaced one increment in the clockwise direction. During the movement of the ratchet wheel 25, the detent member 26 rides over one tooth of the ratchet wheel and engages between that tooth and the next successive tooth to effect precise stopping of the ratchet wheel in its new position.

During upward movement of the operating lever 15, the prongs 34, 35 are resiliently stressed and upon release of the operating lever, the spring energy is released and functions to restore the operating lever back to its center, nonworking position. This operation is repeated for as many times as necessary to position the timing wheel 20 in the proper position so that the intended number is displayed through the upper window 12. A similar operation is performed on the remaining two operating levers to set the desired ten-minute number and the hour number.

When it is desired to set a different reference time in the digital interval timer, the knob 33 of the operating lever 15 is urged downwardly. causing the main body portion of the lever to pivot about the pin 32 while the prongs 34, 35 are elastically deformed. The pawl 40 is thus moved into engagement with one of the ratchet teeth on the ratchet wheel 29 and functions to angularly displace the ratchet wheel 29 in a counterclockwise direction along with the timing wheel 22 by an increment corresponding to the angle subtended by one ratchet tooth. During counterclockwise movement of the ratchet wheel 29, the detent member 30 rides over one ratchet tooth and engages between that tooth and the next succeeding tooth thereby accurately positioning the timing wheel. This operation is then repeated for as many times as necessary to set the desired number on the reference minute wheel. In a similar manner, the remaining operating levers are repeatedly moved downwardly to set the desired reference time in the reference time-indicating system.

As is well-known in the art, when the time indicated by the time-indicating system corresponds to the reference time set in the reference time-indicating system, the timer is actuated to provide an output signal indicating that the reference time has been detected. One type of system which may be used to respond to the coincidence between the time displayed by the timeindicating system and the reference time-indicating system is disclosed in U.S. Pat. application Ser. No.

307,865 filed concurrently herewith and entitled TIME-DETECTING SYSTEM FOR A DIGITAL TIMER. In the related application, a shaft is automatically moved in the axial direction when the reference time is detected and the movement of the shaft is used to close a switch. The switch may be connected in series with any desired electrical appliance so that the applicance may accordingly be controlled.

Another embodiment of a time-setting device for setting the time wheels in a digital interval timer is shown in FIG. 3. In this embodiment, the operating lever 45 is composed of rigid, inelastic material and includes a pair of lever amrs 46, 47 each extending outwardly from the main body portion of the perating lever towards respective ones of the ratchet wheels 25, 29. At the end of the lever arm 46 is a pivotal pawl member 48 and the pawl is resiliently urged against a stop pin affixed to the lever arm 46. In a similar manner, a pawl member 49 is pivotally mounted at the end of the lever arm 47 and is biased against a stop pin affixed to the lever arm. A biasing spring 50 coacts with the operating lever 45 to resiliently bias same into the middle or nonworking position and the coaction between the biasing spring and the operating lever is described in detail hereinafter with reference to FIG. 6.

When it is desired to change the angular position of the minute timing wheel 20, the operating lever 46 is manually moved upwardly against the biasing force of the spring 50 causing the pawl 48 to engage with the ratchet teeth on the ratchet 25 and angularly displace the ratchet wheel one increment. When the operating lever is released, the resilient energy stored in the biasing spring 50 restores the operating lever to its middle position. During downward movement of the operating lever to its nonworking position, the pawl 48 undergoes pivotal movement in a counterclockwise direction away from the stop pin thereby enabling the pawl to slide over the ratchet teeth on the ratchet wheel. The biasing springs used to bias the pawls is much weaker than the biasing spring 50 used to effect return movement of the operating lever. When it is desired to change the angular position of the minute timing wheel 22, the operating lever 45 is moved downwardly causing angular displacement of the ratchet wheel 29 in a counterclockwise direction in a manner similar to that described above with respect to the ratchet wheel 25.

Two other embodiments of operating levers used in time-setting devices according to the present invention are shown in FIGS. 4 and 5. In FIG. 4, the operating lever 55 is similar to the operating lever 115 shown in FIG. 2 except for the type of biasing means employed for biasing the operating lever into its nonworking position. The operating lever 55 is mounted for turning movement about a pin 56 and a biasing spring 57 biases the lever into its middle, nonworking position. The biasing spring 57 comprises a coil tension spring which extends along the major axis of the operating lever and is continuously mintained in a tensioned condition. Whenever the operating lever 55 is displaced either upwardly or downwardly about the pin 56, the tension spring 57 is further tensioned and upon releas of the operating lever, the tension spring will restore the operating lever to the position shown in FIG. 4.

The operating lever 60 shown in FIG. 5 is composed of elastic material and'depends upon the spring action occurring within the lever arms for restoring the operating lever to its nonworking position. The operating lever 60 is mounted for pivotal movement about a pin 61 and has a pair of lever arms 62, 64 each terminating at its distal end in a pawl member. A projection 65 outwardly from the arm 62 and a similar projection 66 extends outwardly from the arm 64. The projections are dimensioned to simultaneously engage with the interior surface of the front plate II when the operating lever 60 is in its middle, nonworking position, as depicted in solid lines in FIG. 5.

When the operating lever is moved upwardly about the pin 61, the projection 65 is moved out of contact with the front plate III while the projection 64 is urged more strongly against the front plate 11 causing resilient flexure of the lever arm 64 and this position of the operating lever is shown in phantom lines in FIG. 5. When the operating lever 60 is released, the spring energy stored in the lever arm 64 effects return movement of the operating lever to its nonworking position. A similar action occurs when the operating lever is moved in a downward movement about the pin 611.

FIG. 6 discloses the type of biasing spring connection used with the operating lever 45 shown in the FIG. 3 embodiment and FIG. 6 is a rear view of the operating lever shown in FIG. 3. The operating lever has a square flange 52 connected at its rearmost portion and the bi asing spring 50 extends beneath the flange and engages with a pair of support pins 53, 54 which are disposed on opposite sides of the operating lever 45. The pins 53, 54 lie in the same plane as the center of the operating lever 45 when same is centered in its nonworking position. As seen in FIG. 6, if the operating lever 45 is moved upwardly or downwardly, the biasing spring 50 is tensioned and stressed between the support pins 53, 54 so that when the manual actuating force is removed from the operating lever, the biasing spring rapidly returns the operating lever to the nonworking position shown in FIG. 6.

l The time-setting device of the present invention is especially suitable for use in digital interval timers and functions to set either the timing wheels in the timeindicating system or the timing wheels in the reference time-indicating system. The device is relatively simple in construction since the same operating levers are used to actuate the timing wheels in either system and the time correction is effectuated very rapidly by repeatedly flicking the operating leverv either upwardly or downwardly. Many obvious modifications of the timesetting device of the present invention will become apparent to those skilled in the art and the present invention is intended to cover all such obvious modifications falling with the spirit and scope of the present claims.

What we claim is:

ll. In a digital timer having at least one rotatable timeindicating timing wheel containing digital time indicia and at least one rotatable reference time-indicating timing wheel containing digital time indicia; a time setting device for selectively setting the angular positions of said timing wheels comprising an elongated operating lever mounted between said timing wheels for manual pivotal movement in one direction towards one timing wheel and for manual pivotal movement in another direction towards the other timing wheel, biasing means for biasing said operating lever into a middle position intermediate said timing wheels, and means on said operating lever for releasably engaging with said one timing wheel in response to pivotal movement of said operating lever in said one direction to effect angular displacement of said one timing wheel through a predetermined angular increment and for releasably engaging with said other timing wheel in response to pivotal movement of said operating lever in said another direction to effect angular displacement of said another timing wheel through a predetermined angular increment.

2. A digital timer according to claim 1; wherein said last-mentioned means comprises a rotatable ratchet wheel connected to each timing wheel for rotation therewith, and a pair of pawl members connected to said operating lever on opposite sides thereof and each engageable with respective ones of said ratchet wheels in response to pivotal movement of said operating lever in said one and another directions to effect angular displacement of their associated timing wheels.

3. A digital timer according to claim 2; wherein said operating lever has a first lever arm connected thereto and extending outwardly therefrom towards said one timing wheel and a second lever arm connected thereto and extending outwardly therefrom towards said other timing wheel, and means connecting each of said pawl members to the outwardly extending end portions of respective ones of said lever arms.

4. A digital timer according to claim 3; wherein said biasing means comprises a biasing spring connected to one end of said operating lever and extending in the axial direction of said operating lever when same is in said middle position.

5. A digital timer according to claim 3; wherein said biasing means comprises a biasing spring connected to one end of said operating lever and extending transverse to the axial direction thereof.

6. A digital timer according to claim 3; including a pivotal detent member coacting with each ratchet wheel to prevent reverse rotation thereof during return movement of said operating lever to said middle position.

7. A digital timer according to claim 3; wherein said biasing means comprises resilient portions of said first and second lever arms engageable with an abutment surface to maintain said operating lever in said middle position in the absence of an external force and having sufficient resiliency to return said operating lever to said middle position after same has been manually displaced therefrom.

8. A digital timer according to claim 3; wherein said biasing means comprises a pair of resilient prongs extending outwardly from said operating lever cooperative with a pin disposed therebetween to bias said operating lever into said middle position. 

1. In a digital timer having at least one rotatable timeindicating timing wheel containing digital time indicia and at least one rotatable reference time-indicating timing wheel containing digital time indicia; a time-setting device for selectively setting the angular positions of said timing wheels comprising an elongated operating lever mounted between said timing wheels for manual pivotal movement in one direction towards one timing wheel and for manual pivotal movement in another direction towards the other timing wheel, biasing means for biasing said operating lever into a middle position intermediate said timing wheels, and means on said operating lever for releasably engaging with said one timing wheel in response to pivotal movement of said operating lever in said one direction to effect angular displacement of said one timing wheel through a predetermined angular increment and for releasably engaging with said other timing wheel in response to pivotal movement of said operating lever in said another direction to effect angular displacement of said another timing wheel through a predetermined angular increment.
 2. A digital timer according to claim 1; wherein said last-mentioned means comprises a rotatable ratchet wheel connected to each timing wheel for rotation therewith, and a pair of pawl members connected to said operating lever on opposite sides thereof and each engageable with respective ones of said ratchet wheels in response to pivotal movement of said operating lever in said one and another directions to effect angular displacement of their associated timing wheels.
 3. A digital timer according to claim 2; wherein said operating lever has a first lever arm connected thereto and extending outwardly therefrom towards said one timing wheel and a second lever arm connected thereto and extending outwardly therefrom towards said other timing wheel, and means connecting each of said pawl members to the outwardly extending end portions of respective ones of saiD lever arms.
 4. A digital timer according to claim 3; wherein said biasing means comprises a biasing spring connected to one end of said operating lever and extending in the axial direction of said operating lever when same is in said middle position.
 5. A digital timer according to claim 3; wherein said biasing means comprises a biasing spring connected to one end of said operating lever and extending transverse to the axial direction thereof.
 6. A digital timer according to claim 3; including a pivotal detent member coacting with each ratchet wheel to prevent reverse rotation thereof during return movement of said operating lever to said middle position.
 7. A digital timer according to claim 3; wherein said biasing means comprises resilient portions of said first and second lever arms engageable with an abutment surface to maintain said operating lever in said middle position in the absence of an external force and having sufficient resiliency to return said operating lever to said middle position after same has been manually displaced therefrom.
 8. A digital timer according to claim 3; wherein said biasing means comprises a pair of resilient prongs extending outwardly from said operating lever cooperative with a pin disposed therebetween to bias said operating lever into said middle position. 